U.S. Secretary of State John Kerry, center left, and other foreign ministers reach a deal in Geneva last month. / Martial Trezzini, Keystone, via AP

by Danny Danon, USATODAY

by Danny Danon, USATODAY

The interim agreement signed in Geneva between Iran and the P5+1 powers is a bad deal. This agreement does not remove one centrifuge from Iran. Instead, we are beginning to see the dismantling of the very sanctions framework that forced the ayatollahs to finally come to the table in the first place. More importantly, a firm and clear ultimatum has not been made to the Iranians so that they understand what the repercussions will be if they do not fully dismantle their nuclear military program when the current deal expires in six months.

This past November the United States and its friends around the world marked 50 years since President John F. Kennedy's assassination. Kennedy's finest moment in foreign policy was when he proved during the 1962 Cuban Missile Crisis that in dealing with a belligerent and murderous regime, a clear ultimatum is the most effective policy instrument in a leader's toolbox.

When the Soviet Union decided to place nuclear missiles just 100 miles from Florida, Kennedy realized he had three main possibilities from which to choose. One option was to invade Cuba to ensure that Fidel Castro would completely stop the preparations for the missile sites. While this step was recommended by most of his military advisers, Kennedy was not eager to see a repeat of the failed Bay of Pigs fiasco.

A second possibility was to decide that the United States could live with Soviet nuclear missiles in Cuba. Though some argued that 40 more missiles did not constitute a real challenge in the U.S.-Soviet "balance of power," Kennedy correctly assessed that in addition to the real danger posed by these missiles, such a move would set dangerous precedent and allow the Soviets future possibilities to threaten the U.S..

A third course of action â?? one that was adopted by Kennedy â?? was to draw a clear line in the sand. The United States, together with its allies throughout the Western Hemisphere, proclaimed a "quarantine" on Cuba. While one step short of a blockade which would could have been misconstrued as a declaration of war, the quarantine banned any offensive weapons and other dangerous materials from entering Cuba. Moreover, the U.S. announced that they reserved the right to board and inspect any ships approaching Cuba to enforce the quarantine.

On a number of occasions during this crisis the two superpowers came to the brink of nuclear war. In the end, however, it was the U.S. insistence on a steadfast policy that led to a peaceful resolution. When the Soviets realized that a clear line had been drawn in the sand they were willing to negotiate in a serious manner and eventually removed the missiles that had triggered the crisis in the first place.

This is what the international community must do today with Iran if they hope to remove the possibility of the ayatollahs obtaining nuclear weapons. Like the Soviet Union during the Cold War, Iran is a brutal dictatorship bent on spreading its dangerous ideology around the globe. This constitutes a real threat to the entire free world. Despite the wishful thinking of some of our allies, Iran will continue on this dangerous path unless it is confronted with steady resolve and a clear indication of what will not be tolerated.

For obvious reason, this column would not be the appropriate venue to detail the exact message that should be discreetly conveyed to the Iranians. What I can say is that this ultimatum could be a particular point in the development of their nuclear program that the world will not allow them to reach, or it could be a date on the calendar by which point they must commit to completely dismantle their nuclear program or face the severe consequences. Either way it must be understood by the Iranians beyond a doubt that the international community will act harshly once this moment in time has arrived.

Some have argued that the current agreement is a step in the right direction. Unfortunately, I do not see it this way. Vague words describing "options on the table" will not suffice as few seem to take them seriously any more.

The international community should clarify that the farce that was signed in Geneva was merely a first step and the more serious negotiations with the Iranians are to begin now. The international community is in agreement that a nuclear armed Iran is a threat to world peace. Therefore, the only chance at reaching the diplomatic solution that all truly peace-loving nations hope for is to state clearly what lines cannot be crossed, and what the implications will be should the Iranians do so.

Danny Danon is Deputy Defense Minister of Israel and the author of Israel: The Will to Prevail.